Expansion valve for refrigerating apparatus



F. J. HEIDEMAN.

EXPANSION VALVE FOR REFRIGERATING APPARATUS.

APPLICATION FILED J N, 30. 1920.

1,428,081. I nt dSep 5,1922.

Petente em. 5, 1922.

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ASSIGNMENTS, '10 HOUSEHOLD UTILITIES CORPORATION, OF DETROIT, MIOEIGAN,

A CORPORATION OF DELAWARE.

mPANSllION VALVE FOR REFRIGERATING APPARATUS.

Application filed January 30, 1820. Serial No. 355,054.

To all. whom it may concern:

Be it known that I, FRED J. HnInnMAN, a citizen of the United States, residln at Detroit, in the county of Wayne and tate of Michigan, have invented a new and useful Expansion Valve for Refrigerating A pparatus,'of which the following is a specification. 4 p

This invention relates to expansion valves for refrigerating apparatus, and more particularly for small thermostatically controlled refrigerating plants for household use.

The invention'consists primarily in the formation of a difi'erentially stressed diaphragm and in the employment of a spring reinforcing member for said diaphra through which automatic control of t e valve is exercised, a more satisfactory functioning of the diaphragm being. thus secured.

'The invention further consists in the va-, rious features and arrangement of parts hereinafter fully described and illustrated in the accompanying drawing wherein,

, Fig. 1 is a view in side elevation of the valve.

Fig. 2' is a vertical sectional view of the samei Fig. 3 is an interior-view of the diaphragm prior. to its engagement with the valve casing.

In these views the reference character 1 designates a portion of the refrigerating apparatus which serves as a support for the expansion valve, this Iportion preferably being the brine tank. he casing of the valve comprises a sheet metal diaphragm 2 having a down-turned peripheral rim 3, and a cast metal base member 4 having-an upwardly projecting rim 5 formed exteriorly with an annular bead 6 over which the loweredgeportion of the diaphragm rim 3 is rolled, as indicated at 7. A circular cham- .45

her 8 is formed between the members 2 and 4, and the latter member is provided with inlet and outlet passages for said chamber, numbered 9 and 10 respectively. The outlet passage 10 extends through a lug .or bossber 13 is of hemisphericalshape and is dissecuring the hub .15

. pressure conditions there encountered cau posed in the passage 9 centrally beneath the chamber 8, normally closing an upturned outlet 1a of said passage, which forms an nlet port for said chamber 8. The stem 15 of said valve member passes upwardly through the port 14, chamber 8 and diaphragm 2, and is threaded for adjustment through a hub 15 which centrally survmounts the diaphragm: To insure against leakage around said stem, a packing nut 16 engages the outer end of the hub and compresses suitable packing 17 about the stem. he stem 1s (passed through said packing nut and its en is squared, as indicated at 18, for engagement by a wrench or the like.

Within the chamber 8 there is disposed a fiat upwardly dished leaf spring 19 reinforcing .the diaphragm 2, and having the shape of a star or spider, as is'best disclosed in Fig. 3. The several radial arms of said sprlng bear upon, the rim 5 and the center portion-bears against the center of thediaphragm and isrigidly secured thereto. It is preferred to employ'a common means for and said spring to the diaphragm, this being accomplished by extending a reduced end portion of the hub centrally through. the diaphragm and EMAN, or DETROIT, MICHIGAN, nssrcnon, BY manor AND mm spring, and u setting said portion to endepression 21 in the interior face of the diaphragmadjacent said rim, thus weakening such portion and effecting a diiferentiaL stressing of the diaphragm which renders it more effectively flexible, throughout the greater area thereof;

,As will be readily understood by persons familiar with this art, at intermittent periods a pump (not shown) sets up a suction or sub-atmospheric pressure in the chamber 8, and delivers .a liquid refrigerant to the passage 9. When such conditions exist the diaphragm is inwardly deflected (due to the greater exterior pressure exerted by the atmosphere) and the valve 13 is unseated, permitting avery limited flow ofthe liquid refrigerant into the chamber 8. The low an immediate transformation of the liquid into gas, and as such it is withdrawn through the passage 10. During idle periods the spring reinforces the stresses acting in the diaphragm, itself, to insure an outward deflection of the latter, and the consequent seating of the' valve member. Heretofore ithas been uite a delicate matter to mount the diap ragm so that the ance with the present invention, the outward or return movement of the diaphragm is assured, even though it may be deflected beyond its intermediate position. Furthermore, the diaphragm, when so formed and reinforced, may be made more readily responsive to a pressure differential, being proportioned to flex more readily than is feasible where the internal stresses of the diaphragm are alone relied upon to eflect its return movement.

What I claim is:

1. In an expansion valve for refrigerating apparatus, a casing having an expansion chamber and an inlet thereto and outlet therefrom, and a diaphragm forming a wall of said chamber, a valve controlling said inlet, actuable by said diaphragm, and normally seated thereby, and a spring within said chamber acting on said diaphragm and assisting its return to normal after deflection.

2. In an expansion valve. for refrigerating apparatus, a casing having an expansion chamber and an inlet thereto and outlet therefrom, and a diaphragm forming a wall ofsaid chamber, a valve controlling said inlet, actuable by said diaphragm, and normally seated thereby, and a spider-shaped spring within said chamber acting on said eat diaphragm and assistin its return to normal after deflection, sai spring being centrally secured to said diaphragm and peripherally bearing upon the casing.

3. In an expansion valve for refrigerating apparatus, a casing having an expansion chamber and an inlet thereto and outlet therefrom, and a diaphragm forming a wall chamber and an inlet thereto and outlet' therefrom, and a diaphragm forming a wall of said chamber, a valve controlling said inlet, actuable by said diaphragm and normall seated thereby, a stem for said valve passing through the diaphragm, a hub exteriorly surmounting the diaphragm, in

which hub said stem is adjustable, a spring within said chamber resisting deflection of the diaphragm from normal and assisting the return movement thereof, and a common means for securing said hub and said spring to said diaphragm. Y

5. An expansion valve for refrigerating apparatus comprising a casing having an expansion chamber formed between two members, one of which has an intake and 'an outlet passage for said chamber and the other is in the nature of a flexible diaphragm, a valve controlling said inlet passage, a connection between said valve and diaphragm for actuating the former from the latter, and a spider shaped dished spring within said chamber centrally bearing against said diaphragm and peripherally engaging the other member of the casing, said spring assisting the diaphragm in its return to normal position. I

In testimony whereof I sign this specification.

FRED J. HEIDEMAN. 

